When you read about a fairy-tale cottage in the woods, you can just imagine moss growing on the roof. While this image fits well inside the pages of a book, any moss you find on your roof presents a problem. Moss can destroy asphalt or cedar roofs because the moss holds moisture against your roof, which can promote rot. Thus, whenever you see moss starting to grow on your roof, you should remove it immediately and take steps to prevent future invasions.

How to Remove Moss

If you have live moss on your roof, then you must first kill it. The problem is that the roots that hold the moss in place will resist your attempts to tear the moss off your roof. You can tell that moss is alive because it will be moist and green in color. Spray live moss with an oxygen-based bleach rather than chlorine bleach. Any chlorine that runs off your roof can kill plants growing below your roof. Give the bleach time to work, then sweep the moss off of your roof with a broom. Make sure you only use downward strokes with the broom, because sweeping upwards can catch the bottom edge of shingles and cause damage. 

How to Prevent Future Moss Growth

If moss grows on your roof once, you should take it as a sign that your roof is susceptible to future moss invasions. To protect your roof, you will need to first remove any tree branches that hang low over your roof. Trees will shade your roof and release water vapor through the process of evapotranspiration. In this way, trees will promote moss growth. If you live in an area that is prone to precipitation or high levels of humidity, then you will also need to install zinc flashing along the ridge of your roof. When exposed to precipitation, the flashing will release metal salts that act as a natural herbicide and will prevent new moss growth from taking root on your roof. 

Don't be deceived by the quaint, story-tale look of moss. It is not a welcome addition to your roof; instead, it is an agent that will bring on the premature demise of your roof. If you live in an arid climate, then you may never have to worry about moss growth on your roof, but if you live in a wet climate, you should end your fight with moss before it starts by installing zinc flashing along the ridge of your roof. 

For more information, or for help with this project, contact a local roofing company like Absolute Roofing